Conventionally, there is known an oil supply control device for controlling oil supply to each part of an engine. For example, Patent Literature 1 discloses a technique, in which viscosity characteristics of oil are specified from a response speed and an oil temperature when a hydraulic operation of a hydraulically operated variable valve timing mechanism is started, a learning value of viscosity characteristics stored in a storage unit is updated based on the viscosity characteristics, and the learning value of viscosity characteristics is reflected to control of the hydraulically operated variable valve timing mechanism for accurate operation control.
Further, Patent Literature 2 discloses a technique, in which a plurality of hydraulic actuating devices such as a hydraulically operated variable valve timing mechanism and a valve stopping device are provided, and a discharge amount of a capacity variable oil pump is controlled to a target hydraulic pressure at which a hydraulic actuating device is activated depending on an operating state of an engine with use of a regulator valve.